When my first lab was a puppy, I walked, walked, walked him for miles and miles every day, played soccer with him in our yard, and he was still very energetic. I clearly remember a neighbor asking how old he was and at the time he was about 8 months old. The neighbor chuckled and said if I could hold on for 2 years, I would have a really nice dog on my hands. Two. years. It seemed like a lifetime back then and I felt a bit discouraged. Eventually he did calm down and has really been a great, calm, friendly boy. Our second lab calmed down much sooner than our first pup but she had an older "brother" to play with and by then I was an experienced lab Mom.
I think in some of your previous posts people have suggested getting a crate for your pup to stay in when you are not home. Are dog crates available where you are? At 6 months, you have missed some time that could have been spent training him to go into a crate and remain there calmly for a few hours at a time while you are not home to watch him but it's not too late! Crates are very helpful in that most pups do not like to pee or poop where they have to rest or eat, so house training goes pretty quickly. Also, if your pup is in a crate when you're not home, you don't have to wonder if he's eating wires or socks or chewing rugs or tearing up sofa cushions because he cannot get to them. It keeps them safe. You cannot leave them in the crate for hours and hours every day, you still need to feed and exercise him before he goes into the crate in the morning, assuming you work or go to school during the day. You cannot stay out late after work or school without going home to make sure he gets to go outside, get more exercise, gets fed, either by you or a responsible family member or someone you hire to come let him and and walk him. My older lab had to be in a crate during the day until he was about 3 years old, my younger one was trustworthy by the time she was one year old. They do demand your time and attention just like a human baby would, you just can't put a human baby into a crate and leave!
Our first 2 dogs were littermates, we did not know about crates. It took FOREVER for them to not pee in the house, I mean at a year of age they would still have accidents, and in the meantime they tore up sofa cushions, pillows, chewed on the kitchen cabinets, chewed up dry wall that was stacked and waiting to be put up in our basement. Once we learned about crates, got a couple, trained them to go in and relax in there, we all were much, much happier. There are some pups who are never trained to go into a crate but I am a strong advocate of training your pup to be comfortable in a crate when you cannot be home to supervise.
It can be a big challenge. I'm sure your pup loves you, particularly if you are the source of his meals! He's still a baby, even if he's nearly his full size. He's still learning what you want of him, he's still got all that puppy energy and it's going to last for a while yet. Are there dog obedience classes you can take him to? They can be very helpful in developing a good relationship with your dog, too. We've had 7 dogs and even though I know how to train the basic commands, I always take them to classes to give us a chance to work together with other dogs around, with a trainer who can give us pointers and answer questions.
Good luck, don't be discouraged. Love and patience and consistency all help.